Proceedings: National Silvicultural Workshop - October 5-7, 1999 Kalispell, Montana - USDA Forest ...
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
Proceedings:
United States
Department
of Agriculture
National
Forest Service
Rocky Mountain
Research Station
Proceedings
RMRS-P-19 Silvicultural
Workshop
May 2001
October 5–7, 1999
Kalispell, MontanaBarras, Stanley J., ed. 2001. Proceedings: National silvicultural workshop; 1999 October 5-7; Kalispell, MT.
Proceedings RMRS-P-19. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain
Research Station. 85 p.
Silviculture, as an integrative discipline, must combine management skills with scientific and technical
knowledge in the management of forests and woodlands. While traditionally, silviculturists worked in fine
resolution landscapes, today’s practitioner must look at encompassing both larger geographic areas (adjacent
stands, watersheds, regions, subregions) and wider objectives (trees as well as wildlife, commodities, recreation,
sustainability, biological diversity, air quality, and ecosystem resilience). The 12 papers in this proceedings
explore the past, present, and desired future of silviculture’s role and practice. Examination of disturbance
ecology in ecosystem management includes natural and induced disturbances, and management options.
Discussion of desired future conditions includes the importance of understanding the connection between
ecological values and social values, as well as historic reference conditions as they relate to creating forest plans.
A section on inventory, monitoring, and adaptive management looks at multiresource and multiscale data
assessments and temporal continuity; included are design alternatives and a discussion of how to adapt
silvicultural prescriptions. Case studies throughout the proceedings help the reader understand the practical
applications, the successes, and the need for further work.
Keywords: disturbance regimes, disturbance ecology, landscape, ecosystem management, stand structure,
successional reserves, adaptive management
The Editor
Stanley J. Barras served in a number of positions in the Station, and on two tours in the Washington Office. His
USDA Forest Service Research beginning in 1965 by most recent position was National Program Leader,
conducting research on microorganisms associated with Forest Pathology Research. He retired in January 2000
the southern pine beetle. He has served as Project after 35 years of service.
Leader, Assistant Director in the Southern Research
You may order additional copies of this publication by sending your mailing information in
label form through one of the following media. Please specify the publication title and series
number.
Fort Collins Service Center
Telephone (970) 498-1392
FAX (970) 498-1396
E-mail rschneider@fs.fed.us
Web site http://www.fs.fed.us/rm
Mailing Address Publications Distribution
Rocky Mountain Research Station
240 West Prospect Road
Fort Collins, CO 80526
Rocky Mountain Research Station
324 25th Street
Ogden, UT 84401Proceedings:
National
Silvicultural
Workshop
October 5–7, 1999
Kalispell, Montana
Editor:
Stanley J. Barras, Ph.D.Contents ___________________________________________________________
Page
I: Overview Papers .................................................................................................................................. 1
Russell T. Graham The Role of the Silviculturist at Multiple Scales ........................................................ 3
Barry Bollenbacher
Al Harvey Disturbance Ecology in the Northern Rockies:
Penny Morgan One Perspective ..................................................................................................... 8
J. D. Chew Overview of Developing Desired Conditions:
K. O’Hara Short-Term Actions, Long-Term Objectives .......................................................... 11
J.G. Jones
II: Disturbance Ecology ................................................................................................................................ 17
Robert E. Keane Range and Variation in Landscape Patch Dynamics:
Janice L. Garner Implications for Ecosystem Management ............................................................. 19
Casey Teske
Cathy Stewart
Paul Hessburg
Philip M. McDonald Changes in Plant Communities After Planting and
Gary O. Fiddler Release of Conifer Seedlings: Early Findings ....................................................... 26
Mike Hillis Simulating Historical Disturbance Regimes and Stand
Vick Applegate Structures in Old-Forest Ponderosa
Steve Slaughter Pine/Douglas-fir Forests ......................................................................................... 32
Michael G. Harrington
Helen Smith
Gary W. Miller Vegetative Conditions and Management Options in Even-Age
James N. Kochenderfer Stands on the Monongahela National Forest ........................................................ 40
James Knibbs
John E. Baumgras
III: Achieving Desired Future Conditions ........................................................................................................... 49
Larry Blocker Understanding the Connection Between Historic Range
Susan K. Hagle of Variation, Current Social Values and
Rick Lasko Developing Desired Conditions ............................................................................. 51
Robert Keane
Barry Bollenbacher
Bruce Fox
Fred Samson
Randy Gay
Cynthia Manning
R. Mendez-Treneman Developing Desired Future Conditions With the
S. Hummel Landscape Management System: A Case Study
G. Porterie of the Gotchen Late Successional Reserv ............................................................ 60
C. D. Oliver
IV: Inventory, Monitoring, and Adaptive Management ..................................................................................... 69
W. Henry McNab Preliminary Evaluation of Environmental Variables
F. Thomas Lloyd Affecting Diameter Growth of Individual Hardwoods
in the Southern Appalachian Mountains ............................................................... 71
George Lightner Integrated Inventory and Monitoring ....................................................................... 78
Hans T. Schreuder
Barry Bollenbacher
Kerry McMenus
Lois DeMarco Use of Monitoring and Adaptive Management to
Susan L. Stout Promote Regeneration on the Allegheny National Forest ..................................... 84Section I: Overview Papers
12
The Role of the Silviculturist at Multiple
Scales
Russell T. Graham
Barry Bollenbacher
Abstract—Traditionally, silviculturists have been involved with interspersed across landscapes and planned to occur over
fine resolution landscape assessments. Today, silviculturists are decades and even centuries. Silviculturists are very knowl-
asked to go beyond that scale to look at a wide range of objectives edgeable about vegetation and vegetation dynamics and this
(including wildlife, commodities, sustainability, diversity, and eco- places them in the role of teachers both within their respec-
system resilience) on scales ranging from landscape to adjacent tive organizations and to the general public. To be effective
stands, watershed, regions, and sub-regions. As the issues facing and efficient in prescribing stand level treatments to meet
natural resource management become more complex, more conten- this diverse array of objectives and to fulfill the many other
tious, and more political, assessments will become an integral part obligations of the position, silviculturists need to be involved
of management, putting the silviculturist in a vital role of looking at many different spatial and temporal scales.
over a broad range of temporal and spatial scales.
Scales
There are several different notions of scale and often there
Introduction ____________________ is confusion between geographic extent and data resolution
The practice of silviculture in the United States can trace (Haynes and others 1996). Geographic extent refers to the
its roots to late in the 19th century when Schlich (1896) and area covered by an assessment and resolution describes the
others started organizing the methods and concepts of the amount of detail incorporated in the data describing the
discipline. During the 1900s, silviculturists tended forests geographic extent. Broad-scale (regional) assessments use
using both art and science to meet the objectives of landown- coarse resolution data to address issues for national and
ers (Hawley 1937; Toumey 1928). During this time the regional planning, mid-scale (sub-regional) assessments use
majority of wood products produced in the United States
were used by developing towns and cities throughout the
Western and Midwestern United States (Hutchison 1942).
By the end of the 20th century, the practice of silviculture
entailed developing methods and systems for establishing
Forest Policy Assessments
and maintaining communities of trees and other vegetation
that people value (Nyland 1996; Smith and others 1997). To Forest
develop these systems silviculturists depend on a plethora of History
knowledge including zoology, botany, ecology, physics, wild- Monitoring Decisions
Economics
life, silvics, pathology, soils, engineering, law, economics,
and many others (Nyland 1996). Silviculture evolved, to Forest
become an integral component in the management of forests Law Implementation
and woodlands and is essential to most adaptative manage- Forest
ment models (fig. 1). Management Planning Model
As we begin a new millennium silviculturists are being
asked to design silvicultural systems for diverse objectives
ranging from maintaining and renewing ecosystems to pro- Protection
Silviculture:
Utilization
ducing wildlife habitat and commodities. Moreover, the the art and science
silviculturist is often asked to design systems to sustain the
integrity, diversity, and resiliency of ecosystems. Treat-
Wildlife Pathology Silvics Biometrics Forest
ments are applied to stands to meet these objectives but they
Ecology
need to be placed in context of adjacent stands, landscapes,
and watersheds. Different stand treatments often need to be
Zoology Soils Botany Math Ecology
In: Barras, Stan J., ed. 2001. Proceedings: National Silvicultural Workshop;
1999 October 5-7; Kalispell, MT. Proc. RMRS-P-00. Ogden, UT: U.S. Depart- Figure 1—Silviculture is an integrative discipline well
ment of Agriculture, Forest Service, Rocky Mountain Research Station. founded in the basic sciences. This knowledge combined
Russell T. Graham is Research Forester, Forest Service, Rocky Mountain with management skills and technical knowledge make
Research Station, 1221 South Main, Moscow, ID. Barry Bollenbacher is
Regional Silviculturist, Forest Service, Northern Region, Missoula, MT. the practice central to the management of forests and
woodlands (adapted and modified from Nyland 1997).
USDA Forest Service Proceedings RMRS-P-19. 2001 3midresolution data to address issues at the state and re- assessment. This assessment described the social, economic,
gional planning levels, and fine resolution data in small terrestrial, aquatic, and landscape components covering
scale (landscape) assessments are used for Forest and Dis- 23.6 million acres of the inland Northwestern United States.
trict planning. In addition to these spatial scales, temporal Coarse resolution data were used in this assessment cover-
scales ranging from minutes (measured in seconds) to mil- ing the majority of the Columbia River Basin. The assess-
lenniums (measured in centuries) can be used to describe ment was organized around multiple watersheds and the
natural resources. Depending on the issue, location, or need, detail of information reported was in the order of 250 acres
a variety of scales can be displayed in assessments to inform for landscape elements (in other words, vegetation) and
the public about decisions on natural resource management. states and counties for economic and social elements (in
other words, income, population) (fig. 2) (Quigley and others
1997; Hann and others 1997).
Assessments In contrast to the large continental and world assess-
Assessments have always been part of forest manage- ments, the issues addressed at regional scales are more
ment. At a local level silviculturists used exam to design specific but still relatively general. Issues such as ecosystem
stand treatments, while wildlife biologists used habitat health, areas or wildlife at risk, sustainability, or long-term
surveys and animal censuses to plan hunting seasons and productivity are often addressed at this broadscale. The
habitat improvement projects. But it became apparent that information produced at these scales usually draws conclu-
the cumulative effects of these local management actions sions and makes inferences about large areas or subunits of
and the ever expanding resource issues facing today’s man- large areas. For example, the ICRB assessment divided the
agers crossed jurisdictional and ecosystem boundaries interior Columbia River Basin into 13 ecological reporting
(FEMAT 1993). The protection of northern spotted owl (Strix units (ERU) each having similar terrestrial and aquatic
occidentalis caurina) habitat, the harvesting of temperate characteristics. Data were summarized for each ERU and
rain forests, and the protection of anadromous fish habitat conclusions drawn about the ecological condition of each
in the Columbia River Basin are examples of these kinds of area. Similarly, the ICRB assessment used 164 subbasins
contentious resource management issues. Therefore, to make for addressing ecological integrity and landscape patterns
informed natural resource decisions the need for under- (fig. 3). In addition to describing common attributes, these
standing and addressing these issues requires assessments broad-scale assessments can identify unique features that
at and across different spatial and temporal scales. may provide development opportunities or be areas of con-
At the largest geographic extent or the broadest scale, cern needing special care or protection. For example, the
assessments describe resources and conditions at sub-conti- broadscale assessment of the ICRB identified stream reaches
nental, continental, and global scales. Global warming, dispersed throughout the Basin that were key salmonid
world climate, ocean temperature, or ozone assessments fall strongholds potentially needing protection (Lee and others
into this category. Satellite technology, large-scale models, 1997).
or even expert knowledge are used to complete these assess- Using midresolution data, subregional assessments are
ments. They use coarse resolution data and are used for often conducted covering states or smaller areas (fig. 4). The
national and international planning (Hulme and others
1999).
Regional assessments are used for national and regional
planning and cover millions of acres (table 1). Forest health,
catastrophic wildfire, anadromous fisheries, community sta-
bility, and timber harvests were only some of the issues
addressed by the Interior Columbia River Basin (ICRB)
Table 1—Attributes and characteristics typically associated with different
kinds of ecological assessments.
Attribute Assessment
Region Regional (broad), sub-regional (mid),
landscape (small)
Size (acre) Millions to billions, thousands to millions,
tens to thousands
Geographic River basin, multiple watersheds, watershed(s)
extent
Organizational Multiple watersheds, watershed, streams,
hierarchy and vegetation patterns
Data resolution >250 acres (coarse)extent of these assessments usually covers multiple water-
sheds with landscape elements displayed with resolutions
less than 250 acres and socioeconomic elements commonly
derived from county data (table 1). The map scales used in
these assessments can range from 1:24,000 to 1:100,000.
The issues addressed at this scale are similar in nature to
those addressed at the broader scale, but they are usually
more specific. For example, instead of addressing general
questions about plants or animals, mid-scale assessments
may address one species such as the northern goshawk
(Accipiter gentilis) or one ecosystem such as the pinyon/
juniper (Pinus edulis/Juniperus osteosperma) woodlands
(Graham and others 1999b). At these mid-scales, present
and predicted ecosystem conditions are commonly displayed
as are more specific descriptions and locations of vegetation,
species, communities, and risks.
Silviculturists, biologists, and most resource managers
and specialists are most comfortable collecting and analyz-
ing fine resolution data over watersheds, stands, and other
Figure 3—Ecological integrity was rated for watersheds small areas (table 1). These landscape assessments are
throughout the interior Columbia Basin. The silviculturist ordinarily conducted at the District and Forest level within
has the knowledge experience to be involved in these the Forest Service to plan and implement vegetation, water-
kinds of assessment processes. shed, and range projects. Both landscape and socioeconomic
assessments at this scale are often conducted using fine
resolution data with vegetation sampled using patches less
than 50 acres while economic and social information are
collected using households as the sample unit. Questions
and issues addressed at this scale are usually site specific
such as the location of culverts impeding fish passage in a
particular stream, or describing fire risk near cabins at a
particular lake. For example, the landscape assessment of
the Coeur d’Alene Mountains in northern Idaho determined
the proportion of stands containing western white pine
(Pinus monticola) in watersheds for use in restoration man-
agement strategies (fig. 5).
Figure 4—Mid-scale assessments use medium resolu-
tion data to describe ecosystems and are usually more Figure 5—This map shows the proportion of stands in
specific in the issues they address. This map shows watersheds of the Coeur d’Alene Mountains where west-
nesting habitat in Utah and the silviculturists of Utah were ern white pine is currently present. The silviculturist should
instrumental in developing these nest area ratings. be an active player in these landscape assessments.
USDA Forest Service Proceedings RMRS-P-19. 2001 5Assessment Applicability and invasive species, is very common occurring in all 97 counties.
Broad scale assessments can also be used to set priorities.
Silviculturist Involvement _________ For example, broad scale assessments might show how
wildfire regimes changed, threatening the integrity of vari-
The silviculturist can, and should, play a variety of roles
ous forest and woodland ecosystems. This information can
in assessments. By being involved early and continuously
be used to establish prescribed burning programs or wilder-
through the assessment process, silviculturists can inte-
ness fire plans.
grate their knowledge (displayed in fig. 1) into recommenda-
It is imperative that a silviculturist be involved at the sub-
tions which may become future Forest Plan standards or
regional level because they have the knowledge and integra-
guides. The consequence of not being involved is that stan-
tive skills to be a key player in designing, leading, complet-
dards and guides used to direct forest practices coming
ing, and using midscale assessments. Most importantly the
directly from recommendations developed in assessments
silviculturist can make certain the assessment is used prop-
will not contain their knowledge. Silviculturists prescribe
erly, validate the information presented, and show its value
the majority of the treatments applied to a forest and they
for making informed decisions. Information available at this
need to ascertain that standards and guides affecting treat-
scale can be used to define areas at risk from various threats
ments are ecologically sound and applicable. Moreover, a
and can define management opportunities. For example,
silviculturist can help develop assessment recommenda-
these kinds of data can indicate where vegetation treat-
tions that are not prescriptive (in other words, by defining
ments may reduce the risk of catastrophic wildfire or where
silvicultural systems) but describe desired conditions that
the greatest risk for landslides may occur. Additionally
meet management objectives.
these data can readily be used to plan and implement
Involvement in the assessment process allows silvicultur-
landscape level treatments by not only providing context for
ists to recognize the utility of assessments, which depends
activities, but help define and/or locate landscape level
on the need, issue, scale, and decisions to be made. In
elements such as wildlife travel corridors, late-successional
addition, the silviculturist can insure the findings and data
forest reserves, goshawk foraging areas, or recreation sites.
from assessments are properly applied. In general most
Also at this level, integrated information is often presented
silviculturists, wildlife biologists, hydrologists, and manag-
for which the silviculturist is well qualified to evaluate.
ers are most comfortable collecting, analyzing, and using
These integrative systems include rating ecological integ-
fine resolution data describing stands, stream reaches, or
rity, valuing animal habitat, or defining wildfire risk.
other small areas. Because of this comfort, there is a ten-
Traditionally the silviculturist has always been involved
dency to utilize fine resolution data gathered at small scales
with fine resolution landscape assessments. Since the early
for mid and broad-scale assessments even though fine reso-
1970s, silviculturists have been prime players in Forest
lution data may be inappropriate for use at larger scales
Service Forest Plans or even smaller Unit Plan assessments.
(Graham and others 1999a). When coarse resolution data
Additionally, fine resolution data were often used for small
from broad assessments are used to describe small areas it
areas (Ranger Districts) to develop timber, range, or wildfire
is easy to criticize them as wrong, when in reality they are
plans. These assessments describe resource amounts, tim-
misapplied. Similarly, if the processes, assumptions, and
ber volumes, fuel loading, and other site specific resource
scope of the assessment are not well understood it is easy to
characteristics. Recently (1990s), landscape assessments
assume the assessment is not applicable for addressing a
have been used to address local resource issues such as
certain issue or condition.
Douglas-fir beetle (Dendroctonus pseudotsugae) epidemics
Silviculture is an integrative discipline thus it is critical
or urban interface wildfire hazards. If these assessments
that silviculturists should participate in sub-regional and
apply procedures and concepts similar to those tested and
landscape level assessments (fig. 1). At the broadest scale,
used in subregional or regional assessments, their connec-
the silviculturist needs to be aware of processes and content
tivity, usefulness, and efficiency can be greatly improved. No
of the assessment and understand what contributions these
other person has more knowledge or understanding of the
assessments provide towards planning forest treatments.
data and information collected and analyzed at this scale
Broad-scale assessments, such as the ICRB provide context
than does the silviculturist. It is critical that they be in-
for activities at the Region and Forest level while sub-
volved in assessing forest and woodland resources at this
regional assessments provide context for activities at the
scale.
Forest and District level. By providing context, assessments
In the unlikely event that a completed assessment does
disclose the conditions or circumstances that surround the
not cover the issues a silviculturist is dealing with, or does
situation, proposed treatment, or decision. For example, the
not contain the necessary products to make an informed
context for a Forest Plan amendment defining northern
decision, the procedures, methodology, data, and concepts
goshawk habitat might be the amount of habitat throughout
described in the assessment may be applied to address these
the region and the administrative and native threats to the
short-comings. If no assessment product is available that
existing habitat. Broad scale assessments can also identify
meets the need, the first source of information considered
unique areas such as salmonid strong holds or ecosystems in
should be data collected for an assessment but not reported
peril such as the western white pine and pinyon/juniper
on in the desired manner. For example, the ICRB assess-
systems (Hann and others 1997; Lee and others 1997;
ment produced over 150 data layers of the entire interior
Graham and others 1999b). They can also show how common
Columbia River Basin at a variety of resolutions. These data
a situation may be. For example, in the interior Columbia
are available for summarization and analysis (Quigley and
River Basin cheat grass (Bromus tectorum), an introduced
others 1996). If no data are available for meeting the need,
6 USDA Forest Service Proceedings RMRS-P-19. 2001the procedures, models, concepts, and techniques used in The northern goshawk in Utah: habitat assessment and manage-
assessments are appropriate for developing new informa- ment recommendations. Gen. Tech. Rep. RMRS-GTR-22. Ogden,
UT: U.S. Department of Agriculture, Forest Service, Rocky Moun-
tion. Using techniques similar to those employed in com- tain Research Station. 48 p.
pleted assessments will encourage the compatibility and Hann, Wendel J.; Jones, Jeffrey L.; Karl, Michael G. Sherm;
usefulness of the new information. It is imperative that the Hessburg, Paul F.; Keane, Robert E.; Long, Donald G.; [and
silviculturist be involved with these approaches for develop- others]. 1997. Landscape dynamics of the Basin. In: Quigley,
Thomas, M.; Arbelbide, Sylvia J., tech. eds. An assessment of
ing new information.
ecosystem components in the Interior Columbia Basin and
Portions of the Klamath and Great Basins: Volume II. Gen.
Tech. Rep. PNW-GTR-405. Portland, OR: U.S. Department of
Conclusion _____________________ Agriculture, Forest Service, Pacific Northwest Research Station:
338–1055.
As we enter the new millennium the personnel of the Hawley, R. C. 1937. The practice of silviculture. New York: John
Forest Service are being ask to do more with less. Assess- Wiley and Sons. 252 p.
Haynes, Richard W.; Graham, Russell T.; Quigley, Thomas M., tech.
ments, planning, consultation, consolidation, implementa-
eds. 1996. Framework for ecosystem management in the Interior
tion, monitoring, and litigation are only a portion of the Columbia Basin including portions of Klamath and Great Basins.
items keeping silviculturists occupied daily. Even though Gen. Tech. Rep. PNW-GTR-374. Portland, OR: U.S. Department
there are more duties required of the silviculturist then of Agriculture, Forest Service, Pacific Northwest Research Sta-
there is time, being involved in assessments and under- tion. 66 p.
Hulme, M; Barrow, E. M.; Arnell, N. W.; Harrison, P. A.; Johns, T.
standing their consequences, procedures, data, and infor- C.; Downing, T. E. 1999. Relative impacts of human-induced
mation is critical. As the issues facing natural resource climate change and natural climate variability. Nature. 397:
management become more complex, more contentious, and 688–691.
more political, assessments and their completion and use Hutchison, S. B.; Winters, R. K. 1942. Northern Idaho forest re-
sources and industries. Washington, DC: U.S. Department of
will become an integral part of management. Therefore,
Agriculture. 75 p.
because silviculture is the center of forest and woodland Lee, Danny C.; Sedell, James R.; Rieman, Bruce E.; Thurow, Russell
management, the silviculturist needs to be creative, persis- F.; Williams, Jack E. 1997. Broad-scale assessment of aquatic
tent, and innovative to ensure that they find the time and species and habitats. In: Quigley, Thomas M.; Arbelbide, Sylvia
resources to be involved with assessments over various L., tech. eds. An assessment of ecosystem components in the
Interior Columbia Basin and portions of the Klamath and Great
temporal and spatial scales. Basins, Vol III. Gen. Tech. Rep. PNW-GTR-405. Portland, OR:
U.S. Department of Agriculture, Forest Service, Pacific North-
west Research Station: 1057–1496.
References _____________________ Nyland, R. D. 1996. Silviculture: concepts and applications. New
York: McGraw-Hill. 633 p.
Forest ecosystem management assessment team (FEMAT). 1993. Quigley, Thomas M.; Haynes, Richard W.; Graham, Russell T. 1996.
Forest ecosystem management:an ecological, economic, and so- Integrated scientific assessment for ecosystem management in
cial assessment. Portland, OR: U.S. Department of Interior, U.S. the Interior Columbia Basin. Gen. Tech. Rep. PNW-GTR-382.
Department of Agriculture, [and others]. [Irregular pagination]. Portland, OR: U.S. Department of Agriculture, Forest Service,
Graham, Russell T.; Jain, Theresa B.; Haynes, Richard A.; Sanders, Pacific Northwest Research Station. 303 p.
James; Cleaves, Dave. 1999a. Assessments for ecological stew- Schlich, W. 1896. Manual of forestry, Vol. I. Introduction to forestry.
ardship. In: Sexton, W. T.; Malk, A. J.; Szaro, R. C.; Johnson, N. London: Bradbury, Agnew and Co. 294 p.
C., eds. Ecological stewardship: a common reference for ecosys- Smith, D. M.; Larson, B. C.; Kelty, M. J.; Ashton, P. M. S. 1997. The
tem management, Volume III. Kidlington, Oxford, UK: Elsevier practice of silviculture: applied forest ecology. New York: John
Science Ltd.: 535–549. Wiley and Sons, Inc. 537 p.
Graham, Russell T.; Rodriguez, Ronald L.; Paulin, Kathleen L.; Toumey, J. W. 1928. Foundations of silviculture upon an ecological
Player, Rodney L.; Heap, Arlene P.; Williams, Richard. 1999b. basis. New York: John Wiley and Sons, Inc. 438 p.
USDA Forest Service Proceedings RMRS-P-19. 2001 7Disturbance Ecology in the Northern
Rockies: One Perspective
Al Harvey
Penny Morgan
Abstract—Since early 1900s forestry, ecology and related profes- (Allen and Breshears 1998). However, perhaps the greatest
sions have been aware that external disturbances had important potential for bringing about change in current forests, mostly
effects on the development of vegetation. However, the integral part destabilizing change, will be the backlash from lack of
they play in ecosystem development and sustainability across time physical disturbances during their development (Baker 1992).
and space was largely underappreciated. Failure to provide appro- Thus we have the current dominance of late seral and climax
priate disturbances can place stable and productive species and species, with related health problems, in forests throughout
ecosystems at great risk. Seral western white pine and ponderosa the region (Atkins and others 1999; Harvey and others 1992;
pine are prime examples. Solutions to several critical problems are Monnig and Byler 1992). In effect, lack of physical distur-
available and must be more widely implemented, with the support bance may produce greater and longer lasting biological
of all parties…soon. It is already too late to prevent significant change than the most spectacular of physical disturbances.
losses.
Implications of Changing
Disturbance Regimes ____________
Disturbances Typical of the Inland
Northwest _____________________ Landscape-level changes in disturbance regimes have
ramifications not only from the standpoint of creating cur-
Although fire has been the dominant physical force affect- rent forest conditions (Hann and others 1997; Quigley and
ing the evolution and development of most interior western others 1996; Lemkuhl and others 1994), but also in changing
forests (Arno 1980), many other forces are also active and the history of their development. Since the biotic history of
may be even more important locally, depending on windows forests in the region is relatively short (a few thousand
of opportunity. For example, given proper stand develop- years) we should expect that vegetative communities are not
mental history, localized drought, snow, ice, winds, tip- well enough developed to be stable in the face of substantial
overs, etc., can all incite major changes, including responses change (Whitlock 1992). Thus, we can expect them to be
from native insects and pathogens. The current problem reactive. The lack of, or change in, historical disturbance
with the Douglas-fir beetle (Dendroctonus pseudotsugae regimes has radically altered regional forests, leading to
Hopk.) is a good case in point (Carree 1998). Frequent broadscale conversion of dominant vegetation, primarily
importations of exotic vegetation, insects or pathogens prob- favoring climax species (Quigley and others 1996) but with-
ably were not rare to the region in the past but are obviously out normal successional processes. So, not only are regional
even less so in the face of increasing human activities. White forests outside their historic norms (historic range of vari-
pine blister rust (Cronartium ribicola J. C. Fisch.) is a ability [Morgan and others 1994]), they got there without the
classic example of an import causing far-reaching changes “normal” successional processes that provide specific types
(Harvey and others 1994; Monnig and Byler 1992). Chang- of preceding vegetative and possibly soil developmental
ing climate is not unique to this region (Mehringer 1985), histories. Therefore, current vegetation can be viewed as
but is likely to become more important to future forest largely “off-site,” both spatially and temporally, above- and
management (Franklin and others 1991). Two examples belowground (Harvey and others 1999). That condition is
are: (1) the relatively recent (2,000–2,500 year) appearance likely to have undesirable impacts on the future stability,
of western red cedar (Thuja plicata Donn.) and western productivity and sustainability of these forests.
hemlock (Tsuga heterophlla [Raf.] Sarg.) that accompanied
an increase in temperature and moisture in the region
(Mehringer 1985; Whitlock 1992), and (2) locally moving Current Conditions and Their
ecotones in pinyon-juniper (Pinus edulis Engelm. Juniperus Connection to Disturbances ______
monosperma [Engelm.] Sarg.) and ponderosa pine (Pinus
ponderosa Laws.) woodlands as a result of localized drought Interior forests show large-scale changes in species com-
positions and accompanying above- and belowground struc-
tures and nutrient distributions. For the most part, changes
In: Barras, Stan J., ed. 2001. Proceedings: National Silvicultural Workshop;
1999 October 5-7; Kalispell, MT. Proc. RMRS-P-00. Ogden, UT: U.S. Depart- are characterized by a general shift from open ponderosa
ment of Agriculture, Forest Service, Rocky Mountain Research Station. pine to closed pine and/or Douglas-fir (Pseudotsuga men-
Al Harvey is Supervisory Plant Pathologist (Retired), USDA Forest Ser- ziesii [Mirb.] Franco) stands in dry ecosystems (Covington
vice, Rocky Mountain Research Station, Forestry Sciences Lab., 1221 S. Main
St., Moscow, ID. Penny Morgan is Professor of Forestry, College of Forestry, and others 1994; Gast and others 1991). In moist forests, the
Wildlife and Range Sciences, University of Moscow, ID. change has been from tall, moderately closed pine/larch
8 USDA Forest Service Proceedings RMRS-P-19. 2001(Pinus monticola Dougl. ex. D. Don/Larix occidentalis Nutt.) adaptability and tolerance for endemic insects and patho-
to relatively short closed grand fir/hemlock/cedar (Abies gens (seral species) to one of narrow adaptive capacities
grandis [Dougl. ex. D. Don.]) stands (Byler and others 1994; likely predisposed to stress (climax species), may make
Harvey and others 1994; Moeur 1992; Monnig and Byler these forests highly susceptible to destabilization (Harvey
1992). The lack of fire in dry ecosystems (Covington and and others 1999). In historic forests dominated by seral
others 1994) and the importation of white pine blister rust species, insects and pathogens probably served as stabiliz-
into moist ecosystems (Monnig and Byler 1992) essentially ing agents, removing maladapted late seral and climax
changed the workings of two of the most productive, stable species relatively early in stand development, preserving
and forgiving (in terms of both management and natural only the best of the latter and generally encouraging domi-
disturbances) ecosystems in north America. As a result, nance of the long-lived serals (Harvey and others 1999;
these ecosystems have changed to ones dominated by species Lehmkuhl and others 1994). Such a radical change of en-
not capable of doing so under historic conditions. The lack of demic processes in dominant ecosystems is likely to have far
physical disturbances has now opened the door to major reaching (largely undesirable) effects on the productivity,
biological disturbances! Further, blister rust now also threat- stability and management (or lack thereof) of regional for-
ens many populations of high altitude and southwestern five ests (Atkins and others 1999; Harvey and others 1994, 1999;
needle pines (Keane and Arno 1993; Hawksworth 1990) Monnig and Byler 1992).
Where Are We Headed? __________ A Window to the Future __________
With the possible exception of stands dominated by west- Since we are continuing to lose ground with seral species,
ern red cedar on especially moist sites and ponderosa pine on especially with western white pine and ponderosa pine, it is
dry ones, productivity, value, and stability of seral species evident that current approaches have not been and will not
dominated ecosystems exceeded that of most other species likely be sufficient to restore those ecosystems. This loss has
combinations throughout the heart of the interior west. As become abundantly clear as a result of widespread fire and
a result of frequent actions from a variety of insects and overcrowding in dry forests and from the salvage logging of
pathogens, and related fuel accumulations, dominance by infected western white pine. Large trees infected in the
climax species will likely lead to significant losses in both 1940s and 1950s gradually succumbed to a combination of
productivity and longevity (Harvey and others 1999). the rust and western pine beetle (Dendroctonus ponderosae
The shallow rooted, low and dense crowns of climax Hopkins) during the last 20 years. The largest tree on “white
species (Minore 1979) will lead to more strongly horizonated pine drive” in northern Idaho was removed as a hazard to the
soils with larger accumulations of litter on the surface than public in 1998. In 1975, that area was still deserving of the
characteristic of forests dominated by seral species (Harvey name. Today there is hardly a white pine to be seen there
and others 1999). This can lead to rapid immobilization of and, when was the last time you visited a classic ponderosa
nutrients, especially nitrogen, in surface horizons. Located pine-dominated forest stand in a Douglas-fir habitat type?
at the surface, nutrients are subject to the losses associated Without aggressive intervention, sufficient to change cur-
with any severe disturbance, especially fire. In the absence rent trends, the outlook for many native ecosystems, par-
of disturbance, nutrient tieup can lead to vegetative stagna- ticularly those featuring ponderosa pine and western white
tion, in moist, cool forests, perhaps within a single genera- pine as the primary serals are obviously not good. Although
tion (Bormann 1995; Kimmens 1994). some current efforts have had success and workable solu-
The potential, and perhaps likely ultimate outcome of tions for most problems inherent to both dry and moist
effectively eliminating appropriate disturbances will be for- forests are available (Covington and others 1994; Oliver and
ests dominated by species with high nutrient demands, others 1994a,b; Mutch and others 1993; McDonald and Hoff
where nutrient storage may be increased but cycling rates 1991), they have not been applied broadly enough to sub-
increasingly depressed. This will lead to a cycle of increasing stantially alter present trends. A continuing lack of appro-
stress, with associated endemic insect and pathogen activi- priate disturbance is probably the greatest single threat,
ties creating a domino effect that destabilizes ecosystems with the possible exception of more exotic pests, to future
(excessive mortality and more frequent fire). Thus, this sustainability and productivity of interior western forests.
leads to inappropriate sensitivity to and long-term damage
from the same disturbances that once created a highly
productive and stable forest ecosystem that was well adapted References _____________________
to intrinsic disturbances, including historical fire cycles and
Allen, C. D.; Breshears, D. D. 1998. Drought-induced shift of a
the activities of native insects and pathogens. forest-woodland ecotone: rapid landscape response to a climate
As seral species increasingly lose their ability to attain at variation. Proceedings of the National Acadamy of Science. 25:
least a codominant position, they will lose their ability to 14839–14842.
produce seed. And, without disturbance-related openings, Arno, S. F. 1980. Forest fire history in the Northern Rockies.
Journal of Forestry. 78: 460–465.
any of the shade intolerant seedlings that are produced will Atkins, D.; Byler, J.; Livingston, L.; Rogers, P.; Bennett. D. 1999.
quickly lose out to competition from large numbers (4–6,000 Health of Idaho’s forests: summary of conditions, issues, and
ha (10–40,000 acre)) of shade-tolerants (Graham 1990). implications. Forest Health Protection Rep. 99-4. U.S. Depart-
Perhaps most important in this species conversion process ment of Agriculture, Forest Service, Northern Region.
Baker, W. L. 1992. Effects of settlement and fire suppression on
is a potential change in genetic strategy of the dominant
landscape structure. Ecology. 73: 1879–1887.
conifers (Rehfeldt 1994). This change, from one of wide
USDA Forest Service Proceedings RMRS-P-19. 2001 9Birdsey, R. A. 1992. Carbon storage and accumulation in United Mehringer, P. J. 1985. Late-quaternary pollen records from the States forest ecosystems. Gen. Tech. Rep. WO-GTR-59. Washing- interior Pacific Northwest and northern Great Basin of the ton, DC: U.S. Department of Agriculture, Forest Service. 51 p. United States. In: Bryant V. M.; Holloway, R. G., eds. Pollen Bormann, B. T.; Spaltenstein, H.; McClellan, M. H.; Ugolini, F. C.; records of late quaternary North American sediments. Dallas, Cromack, K. Jr.; Nay, S. M. 1995. Rapid soil development after TX: American Association of Stratigraphic Palynologists: windthrow disturbance in pristine forests. Journal of Ecology. 83: 167–189. 747–757. Minore, D. 1979. Comparative autecological characteristics of north- Carree, Y. 1998. Douglas-fir beetle alert. University of Idaho, western tree species—a literature review. Gen. Tech. Rep. PNW- Cooperative Extension. Woodland Notes. 10(2): 1998–1999. GTR-87. Portland, OR: U.S. Department of Agriculture, Forest Covington, W. W.; Everett, R. L.; Steele, R.; [and others]. 1994. Service, Pacific Northwest Forest and Range Experiment Sta- Historical and anticipated changes in forest ecosystems of the tion. 72 p. inland West of the United States. Journal of Sustainable For- Moeur, M. 1992. Baseline demographics of late successional west- estry. 2: 13–63. ern hemlock/western red-cedar stands in northern Idaho Re- Franklin, J. F.; Swanson, F. J.; E. Harmon, M. E.; [and others]. 1991. search Natural Areas. Res. Paper INT-RP-456. Ogden, UT: U.S. Effects of global climate change on forests in northwestern North Department of Agriculture, Forest Service, Intermountain Re- America. Northwest Environmental Journal. 7: 233–254. search Station. 16 p. Gast, W. R.; Scott, D. W.; Schmitt, C.; [and others]. 1991. Blue Monnig, G.; Byler, J. W. 1992. Forest health and ecological integrity Mountains forest health report—new perspectives in forest health. in the Northern Rockies. Forest Pest Management Rep. 92-7. Special Report. Portland, OR: U.S. Department of Agriculture, Missoula, MT: U.S. Department of Agriculture, Forest Service, Forest Service, Pacific Northwest Region. Northern Region. Graham, R. T. 1990. Silvics of western white pine. In: Burns, R., ed. Morgan, P.; Aplet, G. H.; Haufler, J. B.; [and others]. 1994. Histori- Silvics of forest trees of the United States. Agric. Handb. 654. cal range of variability: a useful tool for evaluating ecosystem Washington, DC: U.S. Department of Agriculture, Forest Ser- change. Journal of Sustainable Forestry. 2: 87–111. vice: 385–394. Mutch, R. W.; Arno, S. F.; Brown, J. K.; [and others]. 1993. Forest Hann, W. J.; Jones, J. L.; Karl, M. G.; Hessburg, P. F.; Keane, R. E.; health in the Blue Mountains: a management strategy for fire- [and others]. 1997. Chapter 3: Landscape dynamics of the basin. adapted ecosystems. Portland, OR: Gen. Tech. Rep. PNW-GTR- In: Quigley, T. M.; Arbelbide, S. J., tech. eds. An assessment of 310. U.S. Department of Agriculture, Forest Service, Pacific ecosystem components in the Interior Columbia Basin and Northwest Research Station. 14 p. portions of the Klamath and Great Basins: Volume II. Gen. O’Laughlin, J. O. 1993. Forest health conditions in Idaho. Report 11. Tech. Rep. PNW-GTR-405. Portland, OR: U.S. Department of Moscow, ID: University of Idaho, Idaho Forest, Wildlife and Agriculture, Forest Service, Pacific Northwest Research Station: Range Experiment Station, Idaho Forest, Wildlife and Range 338–1055. Policy Analysis Group. 244 p. Harvey, A. E.; Graham, R. T.; McDonald, G. I. 1999. Tree species Oliver, C. D.; Ferguson, D.; Harvey, A. E.; [and others]. 1994a. composition change—soil organism interaction: potential effects Managing ecosystems for forest health: an approach and the on nutrient cycling and conservation processes in interior forests. effects on uses and values. Journal of Sustainable Forestry. 2: In: Proceedings, Pacific Northwest Forest and Rangeland Soil 113–133. Organism Symposium; 1998 March 18–20; Corvallis, OR. Gen. Oliver, C. D.; Irwin, L. L.; Knapp, W. H. 1994b. Eastside forest Tech. Rep. PNW-GTR-461. Portland, OR: U.S. Department of management practices: historical overview, extent of their appli- Agriculture, Forest Service, Pacific Northwest Research Station: cations, and their effects on sustainability of ecosystems. Gen. 137–145. Tech. Rep. PNW-GTR-324. Portland, OR: U.S. Department of Harvey, A. E.; Hessburg, P. F.; Byler, J. W.; McDonald, G. I.; Agriculture, Forest Service, Pacific Northwest Research Station. Weatherby, J. C.; Wickman, B. E. 1995. Health declines in 73 p. western interior forests: symptoms and solutions. In: Quigley, T. M.; Haynes, R. W.; Graham, R. T.; [and others]. 1996. Baumgartner, D. M.; Lotan, J. E.; Tonn, J. R., eds. Interior cedar- Integrated scientific assessment for ecosystem management in hemlock-white pine forests: ecology and management; 1993 March the interior Columbia River Basins and portions of the Klamath 2–4; Spokane, WA. Pullman, WA: Washington State University, and Great Basins. Gen. Tech. Rep. PNW-GTR-382. Portland, OR: Department of Natural Resource Sciences: 163–170. U.S. Department of Agriculture, Forest Service, Pacific North- Hawksworth, F. G. 1990. White pine blister rust in southern New west Research Station and Bureau of Land Management. 303 p. Mexico. Plant Disease. 74: 938. Rehfeldt, G. E. 1994. Evolutionary genetics, the biological species, Keane, R. E.; Arno, S. F. 1993. Rapid decline of whitebark pine in and ecology of the interior cedar-hemlock forests. In: Baumgartner, western Montana: evidence from 20-year remeasurements. West- D. M.; Lotan, J. E.; Tonn, J. R., eds. Interior cedar-hemlock-white ern Journal of Applied Forestry. 8(2): 1993. pine forests: ecology and management; 1993 March 2–4; Spo- Lehmkuhl, J. F.; Hessburg, P. F.; Everett, R. L.; [and others]. 1994. kane, WA. Pullman, WA: Washington State University, Depart- Historical and current forest landscapes of eastern Oregon and ment of Natural Resource Sciences: 91–100. Washington. Part I: Vegetation pattern and insect and disease Whitlock, C. 1992. Vegetational and climatic history of the Pacific hazards. Gen. Tech. Rep. PNW-GTR-328. Portland, OR: U.S. Northwest during the last 20,000 years: implication for under- Department of Agriculture, Forest Service, Pacific Northwest standing present-day biodiversity. Northwestern Environmen- Research Station. 88 p. tal Journal. 8: 5–28. McDonald, G. I.; Hoff, R. J. 1991. History and accomplishments of Wickman, B. E. 1992. Forest health in the Blue Mountains: the white pine blister rust research in the USDA Forest Service: influence of insects and disease. Gen. Tech. Rep. PNW-GTR-295. proceedings, IUFRO rusts of pine working party conference; Portland, OR: U.S. Department of Agriculture, Forest Service, September 18–22; Banff, AB. Inf. Rep. NOR-X-317. Forestry Pacific Northwest Research Station. 15 p. Canada, Northeast Region, Northern Forestry Centre. 10 USDA Forest Service Proceedings RMRS-P-19. 2001
Overview of Developing Desired Conditions:
Short-Term Actions, Long-Term Objectives
J. D. Chew
K. O’Hara
J.G. Jones
Abstract—A number of modeling tools are required to go from In addition to considering treatment alternatives for indi-
short-term treatments to long-term objectives expressed as desired vidual stands, we need to consider strategies for applying
future conditions. Three models are used in an example that starts the treatments at landscape scales. Given the number of
with determining desired stand level structure and ends with the acres involved and limited budgets, it is clear that treat-
implementation of treatments over time at a landscape scale. The ments cannot be accomplished in all areas in which they are
Multi-Aged Stocking Assessment Model (MASAM) is used for as- needed. Are some strategies more effective than others? Is it
sessing sustainable stand structures. Simulating Vegetative Pat- more cost-efficient to first treat the plant communities
terns and Processes at Landscape Scales (SIMPPLLE) is initially where it takes the least intervention to achieve desired
applied to assess risks from disturbance processes on the current future conditions, or to treat those that need more treat-
landscape without management treatments, but with fire suppres- ments and costs may be higher? Is it better to treat stands
sion. The frequencies of process occurrence from these simulation whose degree of departure from the desired future condition
results are input into the Multi-resource Analysis and Geographic results in a high probability for a disturbance process versus
Information System (MAGIS), an optimization modeling system, one that has a low priority for a disturbance event regardless
for scheduling activities that reduce these risks and address other of how far it is from the desired future conditions?
management objectives while trying to attain desired future condi- Models and decision support systems can provide infor-
tions. The derived treatment schedules are used in additional mation and analyses to aid managers in addressing these
SIMPPLLE simulations to examine the change in risk of natural questions (Mowrer 1997). Our objective of this paper is to
processes. The resulting economic impacts associated with trying to give an overview of a set of models/tools that can help in
achieve the long-term desired future conditions are finally quanti- designing and applying treatments to achieve desired future
fied by putting not only the final treatment schedule, but also the conditions.
changes from disturbance processes from the final set of SIMPPLLE Our overview uses one stand level model and two land-
runs into MAGIS. scape models, one for simulation and one for optimization.
The stand level model is “Multi-Aged Stocking Assessment
Model” (MASAM) for Western Montana ponderosa pine
(Pinus Ponderosa Laws.) (O’Hara 1996). The landscape
Introduction ____________________ simulation model is “Simulating Vegetative Patterns and
Processes at Landscape Scales” (SIMPPLLE) (Chew 1995
Desired future conditions have been quantified for some 1997). The optimization model is the “Multi-resource Analy-
time at the individual stand level. From the beginning of the sis and Geographic Information System” (MAGIS) (Zuuring
requirement for silvicultural prescriptions we have devel- and others 1995).
oped means to quantify desired future conditions, to commu-
nicate them to others, and to identify what treatments are
necessary to achieve and maintain them. These have always Model Descriptions ______________
been tailored to management objectives. As our manage-
ment objectives have changed so have our desired future The stand level model, MASAM, is used to help quantify
conditions. As our objectives have changed to a focus of and evaluate a variety of multiaged ponderosa pine struc-
restoring ecosystem health and functioning, we have changed tures. MASAM was developed from a study of data from
to scales above the individual stand. We have expanded our western Montana and central Oregon to quantify the dy-
definition of desired future conditions to include the level of namics of multiaged stands and to assess stand growth
disturbance processes that are acceptable and necessary to stocking relationships. The methodology differed from pre-
achieve them. Our techniques and tools for describing and vious whole-stand approaches in several respects: it defined
defining desired future conditions have improved to enable the total available three-dimensional growing space with
us to move from the stand level to the landscape level. leaf area index (LAI); it incorporates age structure by divid-
ing stands into cohorts and determining appropriate grow-
ing space requirements for each cohort rather than for the
entire stand; and it provides flexibility to assess a wide
In: Barras, Stan J., ed. 2001. Proceedings: National Silvicultural Workshop; variety of stocking alternatives.
1999 October 5-7; Kalispell, MT. Proc. RMRS-P-00. Ogden, UT: U.S. Depart-
ment of Agriculture, Forest Service, Rocky Mountain Research Station.
MASAM is a spreadsheet model that requires the user to
J. D. Chew is a Forester and J. G. Jones is a Research Forester, Rocky specify a number of variables, which describe the desired
Mountain Research Station, P.O. Box 8089, Missoula, MT 59807. K. O’Hara future structure condition. These variables include: number
is a professor, University of California, Berkeley, CA 94720.
USDA Forest Service Proceedings RMRS-P-19. 2001 11of cohorts, or age classes, total leaf area index (LAI), number Bitterroot River upward to the Bitterroot Range divide in
of trees per cohort, and percent of LAI per cohort. The values the Selway-Bitterroot Wilderness. Species composition
assigned are a function of management objectives and forest ranges from ponderosa pine, Douglas-fir (Pseudotsuga men-
health considerations. MASAM helps a user to determine if ziesii var. glauca (Beissn.) Franco), and western larch (Larix
a desired structure is sustainable for a given annual growth occidentalis Nutt.) mixtures at the lower elevations, to
rate for a particular site, cutting cycle length or ownership lodgepole pine (Pinus contorta Doug.), whitebark pine (Pi-
objective. If the cutting cycle is too short to regrow the nus albicaulis Engelm.) and alpine larch (Larix lyallii Parl.)
harvested volume, the system is not sustainable. If sufficient at the upper elevations. For this application example we
growing space is not created during the reproduction method have selected the drier, warmer habitat types in the Dou-
treatments, then replacement cohorts will not regenerate glas-fir series (Pfister and others 1977) to focus on. These are
and the desired structure is not sustained. habitat types in which ponderosa pine is a major seral
The simulation model SIMPPLLE is a stochastic model species, but Douglas-fir is the climax species. The current
that predicts changes in vegetation over time and space by composition of the species in this area has only 1 percent in
using a vegetative state/pathway approach. A vegetative pure ponderosa. A mixture of ponderosa pine with Douglas-
state is defined by dominant tree species, size class/struc- fir comprises 44 percent of the stands. Thirty six percent of
ture, and density. These states are grouped by an ecological the area is nonstocked and the remainder is in mixtures of
stratification of habitat type groups (Pfister and others larch, Douglas-fir and ponderosa pine. Within these acres 29
1977). The change between vegetative states is a function of percent of the area is in pole size classes. Thirty six percent
natural disturbance processes, including insects, disease, are nonstocked. Multistory conditions exist on 17 percent of
and fire, and management treatments. The probability of a the area that correspond with the mixture of ponderosa pine
natural process occurring in a given plant community is and Douglas-fir species composition. None of the multistory
determined by attributes of the state it is in, its past structure is pure ponderosa pine.
processes and management activities, the vegetative pat-
tern as identified by its neighboring communities and their
past processes. The probabilities determined for each plant Step 1
community in a landscape are used in a classical monte carlo The first step in the applications of these tools is the
method (McMillan and Gonzales 1965) to simulate the identification of what structure is not only desired but also
location and timing of process occurrence. Once a process sustainable at the stand level. Our concept of desired condi-
occurs for a plant community, logic is used to model its tions for these habitat types that are ecologically sustain-
spread to neighboring plant communities. able are multiaged ponderosa pine stands. Arno and others
SIMPPLLE helps in understanding landscape interaction (1996a,b) reported presettlement ponderosa pine stands in
between disturbance processes, plant community condi- western Montana consisted of low densities in intermediate
tions, and patterns of communities. The system helps us to and large size classes, with very little representation in size
predict probable scenarios of the location and probability of classes below about 4 inches. This age structure was the
insect, disease, and fire processes on the landscape. Treat- result of localized disturbance/regeneration events that al-
ments can be scheduled to change existing conditions and lowed small even-aged groups of trees to become estab-
the pattern of conditions thus having an impact on the lished, and frequent low severity, low intensity surface fires
probability, the origin, and the spread of processes. This that periodically killed or reduced the density of the lower
information can be used to help identify if the desired future canopy while leaving the upper canopy relatively unharmed
conditions for a large number of stands are sustainable. (O’Hara 1996). A MASAM display for a four cohort structure
The optimization model MAGIS is a spatial decision sup- designed for the moderately warm and dry habitat types
port system for planning land management and transporta- within the planning area is shown in figure 1. There are
tion-related activities on a geographic and temporal basis in currently no areas within the habitat types that meet these
the presence of multiple and sometimes conflicting objec- desired future conditions.
tives (Zuuring and others 1995). An objective to maximize or
minimize and other objectives as constraints that must be
achieved are specified, and the system selects the location Step 2
and timing of activities that best meets these specifications
and calculates the effects. The objective and constraints are SIMPPLLE helps to provide the basis at the landscape
selected from the management relationships within MAGIS, scale for understanding the difference between current
which tabulate output quantities, acres with specified char- vegetative conditions and the desired future condition.
acteristics, miles with specified characteristics, costs, and SIMPPLLE was used to model the disturbance processes of
net revenues. Management relationships can be calculated light and severe western spruce budworm (Choristoneura
for an entire planning area, or specific portions such as occidentalis Freeman), mountain pine beetle (Dendroctonus
individual watersheds. ponderosae Hopkins) in both lodgepole pine and ponderosa
pine, root disease (Armillaria sp.), and three intensities of
wildfire: light-severity fire, mixed-severity fire, and stand-
Example Application _____________ replacing fire. Two sets of 20 stochastic simulations of 5
decades were made starting with the current vegetative
The area used for this example is a 58,038-acre planning conditions. One set was made with the only management
unit, Stevensville West Central, in the Bitterroot National activity being fire suppression, the second set without fire
Forest in Western Montana. The area extends from the
12 USDA Forest Service Proceedings RMRS-P-19. 2001You can also read
